HP-65 more on the card reader

[teenix]

Just in case...

The first switch (I believe) turns the motor on, then as the card progresses into the slot, the RW heads are activated by the second switch. Card write will activate only if the PRGM/RUN switch is in he PRGM position AND the card is not sensed by the third switch to be write protected.

Just a matter of seeing the pattern of switches in the slot as the card comes into contact with the nylon balls. Obviously, the unit will have o be disassembled.

The WE pin looks to be an ACT output and would let the CRC chip know the PRGM/RUN switch position. The logic level of this line should change with the switch position.

cheers

Tony